javascript - grouping elements dynamically inside arrays -

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• split array chunks 32 answers

i new javascript. have list of 500 or more items. need split array sub arrays each containing 20 items. i.e 25 arrays if there 500 items , each array containing 20 items. created 25 arrays below:

var firstset=[]; var secondset=[]; ..... 

and populate each of array using loop. in javascript how can make programmatically since main list can return more 500 items in future , each sub array should configured more 20 items in future. best solution fix situation?

as comments say, should split 2 dimentional array:

var mainarray=[1,2,3,4,5,6,7,8,9,10];  function splitarray(arr,qty){     var mainarr=[], subarr=[];     for(var i=0;i<arr.length;i++){         subarr.push(arr[i]);         if( ((i+1) % qty == 0) || i+1==arr.length){             mainarr.push(subarr);             subarr=[];         }     }     return mainarr; }  console.log(splitarray(mainarray,2)); 

this creates 1 array 5 indexes. in each index, have array of 2 elements. groups in [1,2], [3,4], [5,6], [7,8], [9,10]